Poker is a card game in which players wager their chips on the outcome of a hand. There are countless variations of the game, but all share certain essential features. The game is played with a standard 52-card deck. Players place bets in an attempt to win a pot, which may consist of all the bets made on a single deal or the highest-ranked hand. Players may also bluff, in which case they make bets that are less than the value of their actual hand.
In most forms of poker, each player must put into the pot at least as many chips as the previous player did. This is called calling a bet. If a player cannot call the bet (or is unwilling to do so), they must either raise their own bet or else drop out of the hand (by raising their cards into the dealer face-down).
Once everyone has received their two personal cards, there is a round of betting. This is usually started by 2 mandatory bets called blinds, placed into the pot by the players to the left of the dealer.
Once a player has raised their bet or dropped out of the hand, they must forfeit any chips they have put into the pot. This is called equalization, and it is used to prevent any one player from making a larger profit than another by calling all the way to a showdown. When a player equalizes, they can stay in the pot for as long as they want, but they cannot win more than their stake if they do not have a winning hand.